Implantable mesh combining biodegradable and non-biodegradable fibers

ABSTRACT

Disclosed are mesh materials adapted for use in an implantable sling. The mesh materials include biodegradable and non-degradable components that may be adapted to facilitate scar-tissue ingrowth as the biodegradable components degrade.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a Continuation of, and claims priority to, U.S.patent application Ser. No. 11/448,252, filed on Jun. 6, 2006, entitled“IMPLANTABLE MESH COMBINING BIODEGRADABLE AND NON-BIODEGRADABLE FIBERS”,the disclosure of which is incorporated by reference herein in itsentirety.

FIELD OF THE INVENTION

The invention generally relates to surgically implantable supportiveslings. More specifically, in various embodiments, the invention isdirected to mesh slings including biodegradable fibers interwoven withnon-biodegradable fibers. In some embodiments, fibers include bothbiodegradable and non-biodegradable portions. The invention also relatesto methods of use and manufacture of such slings and fibers.

BACKGROUND

Urinary incontinence affects over 13 million men and women in the UnitedStates. Stress urinary incontinence (SUI) affects primarily women and isgenerally caused by two conditions, intrinsic sphincter deficiency (ISD)and hypermobility. These conditions may occur independently or incombination. In ISD, the urinary sphincter valve, located within theurethra, fails to close properly (coapt), causing urine to leak out ofthe urethra during stressful activity. Hypermobility is a condition inwhich the pelvic floor is distended, weakened, or damaged, causing thebladder neck and proximal urethra to rotate and descend in response toincreases in intra-abdominal pressure (e.g., due to sneezing, coughing,straining, etc.). The result is that there is an insufficient responsetime to promote urethral closure and, consequently, urine leakage and/orflow results. Moreover, the condition of stress urinary incontinence isoften compounded by the presence of untreated vaginal vault prolapse orother more serious pelvic floor disorders. Often, treatments of stressincontinence are made without treating the pelvic floor disorders,potentially leading to an early recurrence of the pelvic floor disorder.

These and related conditions, are often treated using an implantablesupportive sling. Such slings may be made from a variety of materials,but are often made from a mesh material. The mesh may be placed, forexample, under the urethra, close to the high-pressure zone with littleor no elevation to the urethra. When abdominal pressure increases, suchas from coughing, sneezing, or the like, the sling facilitates thecollapse of the urethra as a mechanism for closing the urethra toinhibit urine leakage.

Subsequent to implantation, scar tissue typically forms around thesling. This scar tissue further supports the urethra and sphinctermuscle to facilitate complete urethral closure. Clinically, there aretwo major challenges to a successful outcome—the formation of prominentand permanent scar tissue around the sling, and release of the slingtension to accommodate the body growth. There is a need for an improvedsurgically implantable sling that better addresses these two challenges.

SUMMARY OF THE INVENTION

The invention addresses the deficiencies of the prior art by providingan improved implantable sling for supporting an anatomical site in thebody of a patient. More particularly, in various aspects, the inventionprovides a supportive sling formed from a material that encouragesprominent and permanent formation of scar tissue upon sling implantationand optimizes the sling tension post-surgery using a combination ofnon-biodegradable materials with biodegradable materials. According toone feature, as portions of the sling degrade, they are replaced by scartissue, which provides for automatic sling tension attenuation inresponse, for example, to body movement and body growth. According toanother feature, the biodegradable materials are integrated into thesling in such a way that pores/interstitial gaps in the sling enlarge asthe materials degrade, further assisting in tissue in-growth and scartissue formation. According to a further feature, the degradationproducts of the biodegradable materials accelerate tissue inflammationand thus, scar tissue formation onto and/or into the implanted sling.

More particularly, in one aspect, the invention provides a mesh slingincluding a plurality of fibers that are braided, knitted or otherwisewoven together. The sling fibers may be formed from one or morefilaments, which may be made from one or more materials, or may beformed as monofilaments. According to one embodiment, some of the slingfibers are biodegradable, while others are non-biodegradable. In oneconfiguration, the sling has a high biodegradable/non-biodegradableratio in a longitudinal direction. One advantage of this construction isthat as the longitudinal fibers degrade, they are replaced withpermanent and prominent scar tissue. Unlike the original sling fibers,the scar tissue naturally expands and contracts to accommodatephysiological changes, such as body growth and patient movement.According to another advantage of the invention, at least some of thesling fibers are non-biodegradable and remain to enhance the supportprovided by the scar tissue. In this way, the sling fibers initiallyprovide the needed anatomical support, encourage scar tissue formation,and ultimately substantially give way to enable the body's naturaltissues to provide most of the needed anatomical support.

In one configuration, the ratio of biodegradable/non-biodegradablefibers in a longitudinal direction (e.g., a direction extending acrossthe urethra as opposed to along the urethra) is greater than about ¼, ⅓,½, ¾, or 1. In some configurations, the ratio ofbiodegradable/non-biodegradable fibers in a longitudinal direction isgreater than about 2, 3 or 4. According to further configurations, theoverall ratio of biodegradable/non-biodegradable fibers is greater thanabout ¼, ⅓, ½, ¾, 1, 2, 3 or 4.

According to another embodiment, some of the sling fibers are compositefibers including a non-biodegradable core and an outer biodegradablelayer. The composite fibers may be formed, for example, by co-extrusionor by dipping, coating or otherwise treating the non-biodegradable coreto provide the outer biodegradable layer. The composite fibers may beinterleaved with non-biodegradable and/or biodegradable fibers to form asling for supporting a patient's urethra or for supporting the patient'spelvic floor. One advantage of the composite fibers is that as the outerlayer degrades, the size of the pores/interstitial gaps between thefibers effectively increases, providing more room for tissue in-growthand scar tissue formation. The composite fibers may be employed aslongitudinal and/or transverse fibers in the sling of the invention.

According to various configurations, the pores/interstitial gaps betweenadjacent longitudinally extending fibers and/or between adjacenttransversely extending fibers are greater than about 50 micrometers(μm), 75 μm, 100 μm, 200 μm or 500 μm subsequent to degradation of thecomposite fiber outer layer. According to a further configuration, thefibers used to form the mesh sling have an initial diameter of betweenabout 0.005 cm and about 0.1 cm. In some instances, the fibers have aninitial diameter of between about 0.01 cm and about 0.05 cm. Accordingto various constructions, the sling may have an initial width of betweenabout 1 cm to about 4 cm, about 4 cm to about 6 cm, about 6 cm to about8 cm, or larger, depending on the anatomical location to be supported.The slings of the invention may have an initial length of about 4 cm toabout 6 cm, about 6 cm to about 8 cm, about 8 cm to about 12 cm, about12 cm to about 16 cm, or larger, depending on the anatomical location tobe supported.

The non-biodegradable portions of the sling may be fabricated from anyof a plurality of biocompatible materials, such as nylon, silicone,polyethylene, polyester, polyethylene, polyurethane, polypropylene,polyvinyl polymers, fluoropolymers, copolymers thereof, combinationsthereof, or other suitable synthetic material(s). The biodegradableportions of the sling may be derived from mammalian tissue, syntheticmaterials, or a combination of mammalian tissue and synthetic material.According to some configurations, the biodegradable portions of thesling are formed from synthetic polymers, such as polylatic acid,polyglycolic acid, or natural polymers, such as collagen, cellulose,polypeptides, polysaccharides, or copolymers thereof. According to someconfigurations, bioactive compounds or drugs may be added to thebiodegradable polymers to enhance acute inflammation and encourage scartissue formation. Examples of these inflammation promoters arefibrinogen and fibrin.

The sling may incorporate or be coated with one or more agents toprovide a therapeutic effect, for example, to reduce discomfort, toreduce the chance of infection and/or to promote tissue growth.According to some embodiments, the one or more agents may be disposedbetween the sling fibers and/or between the two sling layers.

These and other features, advantages and aspects of the invention aredescribed below with respect to the various illustrative embodiments ofthe invention.

BRIEF DESCRIPTION OF THE DRAWINGS

Various illustrative embodiments of the invention are described belowwith reference to the appended drawings, which may not be drawn to scaleand in which like parts are designated by like reference designations.

FIG. 1 shows an implantable supportive sling including bothnon-biodegradable and biodegradable fibers.

FIG. 2 shows an implantable supportive sling including bothnon-biodegradable and biodegradable fibers.

FIGS. 3A and 3B are conceptual drawings illustrating an exemplary slinghaving biodegradable and non-degradable fibers prior and subsequent todegradation of the biodegradable fibers.

FIG. 4 shows an implantable supportive sling including composite fibershaving a non-biodegradable core and a biodegradable outer layer.

DESCRIPTION OF ILLUSTRATIVE EMBODIMENTS

As described in summary above, in various illustrative embodiments, theinvention is directed to a supportive sling formed from a material thatencourages prominent and permanent formation of scar tissue upon slingimplantation and optimizes the sling tension post-surgery using acombination of non-biodegradable and biodegradable materials.

FIG. 1 shows exploded section 100 a of an implantable supportive sling100 having both non-biodegradable 102 a-102 d and biodegradable 104a-104 f fibers according to an illustrative embodiment of the invention.As shown, in the embodiment of FIG. 1, the biodegradable 104 a-104 f andnon-biodegradable 102 a-102 d fibers are interdispersed with each other.The fibers 102 a-102 d and 104 a-104 f may be, for example, braided,knitted or otherwise woven together. The sling fibers 102 a-102 d and104 a-104 f may be formed from one or more filaments, which may be madefrom one or more materials, or may be formed as mono filaments.According to the illustrative embodiment, the sling 100 has an initialtension and expansion capability when implanted into the body of apatient. Subsequent to implantation, the fibers 104 a-104 f degrade andare absorbed into the tissue surrounding the sling 100. As fibers 104a-104 f are removed from the sling 100, the sling 100 is able tostretch/expand more easily.

According to one aspect, the material used for the fibers 104 a-104 f isselected so as to have a pre-determined rate of degradation, so thattheir degradation is timed to coincide with the growth of permanent andprominent scar tissue on, into and around the sling 100. The scar tissueforms a natural support that takes the place of the degraded fibers 104a-104 f. The scar tissue acts both to maintain the initial supportprovided by the sling 100 and to enable the sling 100 to stretch/expandand contract naturally as may be needed to accommodate physiologicalchanges in the body of the patient, thereby providing for enhanced slingtension attenuation. Such physiologic changes include, for example,weight loss, weight gain, body growth (particularly important whentreating adolescents), and patient movement. According to anotheradvantage of the invention, the non-biodegradable sling fibers 102 a-102d remain to enhance the anatomical support provided by the scar tissue.

According to the illustrative embodiment, the sling 100 has a highbiodegradable/non-biodegradable fiber ratio in a longitudinal direction106 (e.g., a direction extending across the urethra as opposed to alongthe length of the urethra). This feature is particularly advantageouswhen providing urethral support or for supporting the pelvic floor. Forexample, as the longitudinal fibers (e.g., the fibers 104 a-104 f)degrade, they are replaced with scar tissue, which naturally expands andcontracts to maintain the appropriate support under the urethra orpelvic floor, even in light of physiological changes. In oneconfiguration, the ratio of biodegradable/non-biodegradable fibers inthe longitudinal direction 106 is greater than about ¼, ⅓, ½, ¾, or 1,or greater than about 1. In some configurations, the ratio ofbiodegradable/non-biodegradable fibers in the longitudinal direction 106is greater than about 2, 3 or 4. According to further configurations,the over-all ratio of biodegradable/non-biodegradable fibers is greaterthan about ¼, ⅓, ½, ¾, 1, 2, 3, or 4, or greater than about 4.

According to the illustrative embodiment, the sling 100 includes aplurality of pores/interstitial gaps 108 formed between the fibers 102a-102 d and 104 a-104 f. According to 15 various configurations, thediameter of a given pore/interstitial gap 108 that forms betweenadjacent longitudinally extending non-degradable fibers (e.g., fibers102 c and 102 d) and/or between adjacent transversely extendingnon-degradable fibers (e.g., fibers 102 a and 102 b) is greater thanabout 50 micrometers (μm), 75 μm, 100 μm, 200 μm, 500 μm, 1 mm, orgreater subsequent to degradation of the interspersed degradable fibers(e.g., 104 b).

According to a further configuration, the fibers used to form the meshsling have an initial diameter of between about 0.005 cm and about 0.1cm. In some instances, the fibers have an initial diameter of betweenabout 0.01 cm and about 0.05 cm. According to various constructions, thesling may have an initial width of between about 1 cm to about 4 cm,about 4 cm to about 6 cm, about 6 cm to about 8 cm, or larger, dependingon the anatomical location to be supported. The slings of the inventionmay have an initial length of about 4 cm to about 6 cm, about 6 cm toabout 8 cm, about 8 cm to about 12 cm, about 12 cm to about 16 cm, orlarger, depending on the anatomical location to be supported.

According to one feature, the degradation products of the biodegradablematerials accelerate tissue inflammation and, thus, scar tissueformation in the region of the implanted sling.

As shown in FIG. 1, the fibers 102 and 104 are formed in a grid-likepattern, with one or more transverse 102 a and one or more longitudinal102 c fibers extending in the transverse direction 105 (e.g., in adirection along the length of the urethra) and longitudinal direction106. The degradable and non-degradable fibers may extend in either orboth directions 105 and 106. In certain embodiments, the fibers areconfigured as a mesh having a non-degradable grid-like formation withdegradable fibers interwoven through gaps and holes within the mesh.FIG. 2 depicts an example of such an alternative embodiment. The mesh110, which is configured in a grid-like fashion similar to FIG. 1,includes longitudinal 110 a and transverse 110 b strands ofnon-degradable fibers configured in a grid-like fashion. Holes 108 formthe interstitial spaces between the strands, similar to the holes 108shown in FIG. 1. As shown in the embodiment of FIG. 2, biodegradablefibers 112 are woven through the holes 108, extending under and over thestrands 110 a and 110 b and being supported by the strands 110 a and 110b and to rest within the mesh. As described above, as the degradablestrands 112 degrade, the remaining mesh strands become less restrictedand the mesh 110 becomes more elastic, thereby allowing the mesh 110 tostretch and expand more easily. As the fibers 112 degrade, scar tissueforms within the spaces vacated by the strands 112 and forms naturalsupport described above.

FIGS. 3A and 3B depict an alternative configuration of a sling 120having biodegradable and non-degradable components, similar to theslings described above. As shown in FIG. 3A, the mesh 120 hasnon-degradable strands 122 extending in the transverse direction 105(e.g., in a direction along the length of the urethra), and a number ofnon-degradable segments 123 extending between transverse strands, suchas strand 123, in the longitudinal direction 106. The mesh 120 alsoincludes longitudinally extending biodegradable fiber segments 124 a-124h that cross or otherwise pass between transverse fibers in thelongitudinal direction 106. In the depicted embodiment, the degradablesegments 124 a-124 h are positioned adjacent to one or morelongitudinally extending non-degradable fibers (e.g., fiber 124 a ispositioned adjacent to strands 125 and 127). Alternatively, one or moredegradable segments can be positioned adjacent to longitudinallyextending degradable fibers. As shown, various longitudinal degradablesegments, such as 124 a and 124 b, extend in substantially the samelongitudinal path (e.g., both strands 124 a and 124 b extendsubstantially parallel to an exterior edge 120 a of the sling 120) butare spaced apart so as to not contact a common transverse strand. Asshown in FIG. 3B, after degradation of the longitudinally extendingbiodegradable strands 124 a-124 h, large holes 128 are left between thenon-degradable fibers, for example between strands 125 and 127.

The mesh 120 is formed, in one implementation, by attaching thecross-segments (e.g., 124 a and 124 b) to the transverse strands byadhesive, laser welding, or a patterned air-drying technique. Accordingto one embodiment, the air-drying technique begins with dissolving abiodegradable polymer in a solvent, then applying the solvent to anon-biodegradable mesh. Following application of the solvent to themesh, the solvent is allowed to evaporate, leaving the biodegradablepolymer in place and secured to the mesh. The mesh and applied polymermay be air-dried to allow for evaporation of the solvent. In certainembodiments, any suitable method may be used to accelerate evaporationof the solvent from the polymer and mesh, such as machine-drying andapplying heat. According to one feature, the air-drying technique allowsfor precise placement of the biodegradable polymers to selectedlocations on the mesh.

The biodegradable polymer may be applied to the mesh sling in a selectedpattern. For example, the mesh sling may be constructed such that it hasa plurality of apertures spaced along the length of the sling, and thebiodegradable polymer may be applied to the mesh such that it bridgesthe apertures. The biodegradable polymer may be applied to the sling ina plurality of segments, such as segments 124 a-124 h of FIG. 3A, andthe segments may be positioned to form a plurality of v-shapes,triangles, diamond shapes, polygonal shapes, ellipses, circles, or acombination of shapes, extending along at least a portion of the lengthof the sling. The shapes may extend from the center of the sling to anend of the sling. The biodegradable polymer may also be applied aslongitudinal strands extending along a length of the sling, crossingover transverse mesh strands. In other embodiments, the biodegradablepolymer may be applied as transverse strands. According to variousimplementations, the biodegradable polymer may be applied to anyselected section of the mesh sling. For example, the biodegradablepolymer may be applied to the ends of the sling and not to the centerportion of the sling, or the biodegradable polymer may be applied alongthe entire length of the sling.

In certain exemplary implementations, the mesh according to theinvention is formed from fibers that are coextruded or otherwiseconfigured as single strands having both non-degradable and degradablecomponents. FIG. 4 depicts an exemplary embodiment of such a mesh 130.As shown in the exploded cross-sectional view of subsection 134 a of thelongitudinal strand 134, the fibers 132 and 134 of mesh 130 have aninterior non-degradable component 138 disposed within a degradableexterior portion 136. Pores/interstitial gaps 108 form between adjacentlongitudinally extending fibers 134 and/or between adjacent transverselyextending fibers 132. The pores 108 have a diameter greater than about50 micrometers (μm), 75 μm, 100 μm, 200 μm or 500 μm subsequent todegradation of the fiber outer layer 136. In certain embodiments, thepores expand by about 5% or greater, 10% or greater, 25% or greater, or50% or greater upon degradation of the outer layer.

The strand 134 is depicted in subsection 134 a as extendinglongitudinally, though it can also be incorporated in one or more of thetransverse strands 132, allowing the entire mesh 130 to be formed fromstrands of this composite material.

In certain configurations, the composite of mesh 130 is incorporatedwith other mesh embodiments described herein. For example, the compositematerial of mesh 130 may be used to form the degradable segments 124 athrough 124 h shown in FIG. 3A. In such an implementation, as theexterior segment 136 degrades, the thin non-absorbable filaments ofstrand 138, rather than the gaps 128 shown in FIG. 3B, are left behind.The remaining mesh is accordingly more pliable and flexible than priorto the degradation. In another example, one or more of the compositestrands used in mesh 130 are used as the biodegradable strand in mesh100 or 120. In another example, the mesh 130 may incorporate one or moreof strands 102 and 104 of the sling mesh 100, such that the strands 102and 104 are interspersed with strands 132 and 134. In another example,the mesh 130 is configured to include one or more of segments 124 and125 of mesh 120, which impart further initial strength to the mesh 130but allow for subsequent pliability after the degradation.

Exemplary mesh materials include, for example, synthetic materials,natural materials (e.g., biological) or a combination thereof. Thenon-degradable portion of the mesh may be fabricated from any of anumber of non-degradable biocompatible materials, such as nylon,silicone, polyethylene, polyester, polyethylene, polyurethane,polypropylene, fluoropolymers, copolymers thereof, combinations thereof,or other suitable synthetic material(s). The biodegradable component ofthe mesh may be any suitable biodegradable material. The biodegradablematerial may be, for example, a biodegradable synthetic material. Theterm “biodegradable,” is used synonymously with “bioabsorbable” and with“degradable” herein, and refers to the property of a material thatdissolves in the body or is absorbed into the body.

Suitable bioabsorbable synthetic materials include, without limitation,polylactic acid (PLA), polyglycolic acid (PGA), poly-L-lactic acid(PLLA), poly(amino acids), polypeptides, human dermis and decellularizedanimal tissue. Human tissues may be derived, for example, from humancadaveric or engineered human tissue. Animal tissues may be derived, forexample, from porcine, ovine, bovine, and equine tissue sources. Thematerial may be an omnidirectional material, a material that hasequivalent tensile strength from any direction, such as pericardium ordermis. Alternatively, the material may be an oriented material, amaterial that has a single direction where the tensile strength of thematerial is the highest. Oriented materials may include rectus fasciaand/or facia lata.

Exemplary biodegradable polymers, which may be used to form a mesh, inaddition to those listed above, include, without limitation, polylacticacid, polyglycolic acid and copolymers and mixtures thereof, such aspoly(L-lactide) (PLLA), poly(D,L-lactide) (PLA), polyglycolic acid[polyglycolide (PGA)], poly(L-lactide-co-D,L-lactide) (PLLAIPLA),poly(L-lactide-coglycolide) (PLLA/PGA), poly(D,L-lactide-co-glycolide)(PLA/PGA), poly(glycolide-co-trimethylene carbonate) (PGA/PTMC),poly(D,L-lactide-co-caprolactone) (PLA/PCL), andpoly(glycolide-co-caprolactone) (PGA/PCL); polyethylene oxide (PEO);polydioxanone (PDS); polypropylene fumarate; polydepsipeptides,poly(ethyl glutamate-co-glutamic acid), poly(tertbutyloxy-carbonylmethylglutamate); polycaprolactone (PCL), poly(hydroxy butyrate),polycaprolactone co-butylacrylate, polyhydroxybutyrate (PHBT) andcopolymers of polyhydroxybutyrate; polyphosphazenes, poly(phosphateester); maleic anhydride copolymers, polyiminocarbonates, poly[ (97.5%dimethyl-trimethylene carbonate)-co-(2.5% trimethylene carbonate)],cyanoacrylate, hydroxypropylmethylcellulose; polysaccharides, such ashyaluronic acid, chitosan and regenerate cellulose; poly(amino acid) andproteins, such as poly(lysine), Poly(glutamic acid), gelatin andcollagen; and mixtures and copolymers thereof

In various implementations of the invention, the mesh, either as a wholeor on a fiber by fiber basis (e.g., fibers 122, 125, etc.), may includean agent for release into the patient's tissues. One illustrative agentis a tissue growth factor that promotes, when applied to the patient'stissues in a pharmaceutically acceptable amount, well-organizedcollagenous tissue growth, such as scar tissue growth, preferably, inlarge quantities. According to one feature, the agent may or may notblock or delay the dissolvability of the biodegradable materials. Thismay be controlled by selecting differing methods for loading the agentonto the sling. The tissue growth factor may include natural and/orrecombinant proteins for stimulating a tissue response so thatcollagenous tissue such as scar tissue growth is enhanced. Exemplarygrowth factors that may be used include, but are not limited to,platelet-derived growth factor (PDGF), fibroblast growth factor (FGF),transforming growth factor-beta (TGF-beta), vascular endothelium growthfactor (VEGF), Activin/TGF and sex steroid, bone marrow growth factor,growth hormone, Insulin-like growth factor 1, and combinations thereof.The agent may also include a hormone, including but not limited toestrogen, steroid hormones, and other hormones to promote growth ofappropriate collagenous tissue such as scar tissue. The agent may alsoinclude stem cells or other suitable cells derived from the hostpatient. These cells may be fibroblast, myoblast, or other progenitorcells to mature into appropriate tissues.

In various illustrative embodiments, the agent may include one or moretherapeutic agents. The therapeutic agents may be, for example,anti-inflammatory agents, including steroidal and non-steroidalanti-inflammatory agents, analgesic agents, including narcotic andnon-narcotic analgesics, local anesthetic agents, antispasmodic agents,growth factors, gene-based therapeutic agents, and combinations thereof.

Exemplary steroidal anti-inflammatory therapeutic agents(glucocorticoids) include, but are not limited to,21-acetoxyprefnenolone, aalclometasone, algestone, amicinonide,beclomethasone, betamethasone, budesonide, chloroprednisone, clobetasol,clobetasone, clocortolone, cloprednol, corticosterone, cortisone,cortivazol, deflazacort, desonide, desoximetasone, dexamethasone,diflorasone, diflucortolone, difluprednate, enoxolone, fluazacort,flucloronide, flumehtasone, flunisolide, fluocinolone acetonide,fluocinonide, fluocortin butyl, fluocortolone, fluorometholone,fluperolone acetate, fluprednidene acetate, fluprednisolone,flurandrenolide, fluticasone propionate, formocortal, halcinonide,halobetasol priopionate, halometasone, halopredone acetate,hydrocortamate, hydrocortisone, loteprednol etabonate, mazipredone,medrysone, meprednisone, methyolprednisolone, mometasone furoate,paramethasone, prednicarbate, prednisolone, prednisolone25-diethylaminoacetate, prednisone sodium phosphate, prednisone,prednival, prednylidene, rimexolone, tixocortal, triamcinolone,triamcinolone acetonide, triamcinolone benetonide, triamcinolonehexacetonide, and pharmaceutically acceptable salts thereof.

Exemplary non-steroidal anti-inflammatory therapeutic agents include,but are not limited to, aminoarylcarboxylic acid derivatives such asenfenamic acid, etofenamate, flufenamic acid, isonixin, meclofenamicacid, mefanamic acid, niflumic acid, talniflumate, terofenamate andtolfenamic acid; arylacetic acid derivatives such as acemetacin,alclofenac, amfenac, bufexamac, cinmetacin, clopirac, diclofenac sodium,etodolac, felbinac, fenclofenac, fenclorac, fenclozic acid, fentiazac,glucametacin, ibufenac, indomethacin, isofezolac, isoxepac, lonazolac,metiazinic acid, oxametacine, proglumetacin, sulindac, tiaramide,tolmetin and zomepirac; arylbutyric acid derivatives such as bumadizon,butibufen, fenbufen and xenbucin; arylcarboxylic acids such as clidanac,ketorolac and tinoridine; arylpropionic acid derivatives such asalminoprofen, benoxaprofen, bucloxic acid; carprofen, fenoprofen,flunoxaprofen, flurbiprofen, ibuprofen, ibuproxam, indoprofen,ketoprofen, loxoprofen, miroprofen, naproxen, oxaprozin, piketoprofen,pirprofen, pranoprofen, protizinic acid, suprofen and tiaprofenic acid;pyrazoles such as difenamizole and epirizole; pyrazolones such asapazone, benzpiperylon, feprazone, mofebutazone, morazone,oxyphenbutazone, phenybutazone, pipebuzone, propyphenazone,ramifenazone, suxibuzone and thiazolinobutazone; salicylic acidderivatives such as acetaminosalol, aspirin, benorylate, bromosaligenin,calcium acetylsalicylate, diflunisal, etersalate, fendosal, gentisicacid, glycol salicylate, imidazole salicylate, lysine acetylsalicylate,mesalamine, morpholine salicylate, 1-naphthyl salicylate, olsalazine,parsalmide, phenyl acetylsalicylate, phenyl salicylate, salacetamide,salicylamine o-acetic acid, salicylsulfuric acid, salsalate andsulfasalazine; thiazinecarboxamides such as droxicam, isoxicam,piroxicam and tenoxicam; others such as E-acetamidocaproic acid,s-adenosylmethionine, 3-amino-4-hydroxybutyric acid, amixetrine,bendazac, benzydamine, bucolome, difenpiramide, ditazol, emorfazone,guaiazulene, nabumetone, nimesulide, orgotein, oxaceprol, paranyline,perisoxal, pifoxime, proquazone, proxazole and tenidap; andpharmaceutically acceptable salts thereof. Exemplary narcotic analgesictherapeutic agents include, but are not limited to, alfentanil,allylprodine, alphaprodine, anileridine, benzylmorphine, bezitramide,buprenorphine, butorphanol, clonitazene, codeine, codeine methylbromide, codeine phosphate, codeine sulfate, desomorphine,dextromoramide, dezocine, diampromide, dihydrocodeine, dihydrocodeinoneenol acetate, dihydromorphine, dimenoxadol, dimepheptanol,dimethylthiambutene, dioxaphetyl butyrate, dipipanone, eptazocine,ethoheptazine, ethylmethylthiambutene, ethylmorphine, etonitazene,fentanyl, hydrocodone, hydromorphone, hydroxypethidine, isomethadone,ketobemidone, levorphanol, lofentanil, meperidine, meptazinol,metazocine, methadone hydrochloride, metopon, morphine, myrophine,nalbuphine, narceine, nicomorphine, norlevorphanol, normethadone,normorphine, norpipanone, opium, oxycodone, oxymorphone, papaveretum,pentazocine, phenadoxone, phenazocine, pheoperidine, piminodine,piritramide, proheptazine, promedol, properidine, propiram,propoxyphene, rumifentanil, sufentanil, tilidine, and pharmaceuticallyacceptable salts thereof.

Exemplary non-narcotic analgesic agents that may be combined with theslings of the invention include, but are not limited to, aceclofenac,acetaminophen, acetaminosalol, acetanilide, acetylsalicylsalicylic acid,alclofenac, alrninoprofen, aloxiprin, aluminum bis(acetylsalicylate),aminochlorthenoxazin, 2-amino-4-picoline, aminopropylon, aminopyrine,ammonium salicylate, amtolmetin guacil, antipyrine, antipyrinesalicylate, antrafenine, apazone, aspirin, benorylate, benoxaprofen,benzpiperylon, benzydamine, bermoprofen, brofenac, pbromoacetanilide,5-bromosalicylic acid acetate, bucetin, bufexamac, bumadizon, butacetin,calcium acetylsalicylate, carbamazepine, carbiphene, carsalam,chloralantipyrine, chlorthenoxazin(e), choline salicylate, cinchophen,ciramadol, clometacin, cropropamide, crotethamide, dexoxadrol,difenamizole, diflunisal, dihydroxyaluminum acetylsalicylate,dipyrocetyl, dipyrone, emorfazone, enfenamic acid, epirizole,etersalate, ethenzamide, ethoxazene, etodolac, felbinac, fenoprofen,floctafenine, flufenamic acid, fluoresone, flupirtine, fluproquazone,flurbiprofen, fosfosal, gentisic acid, glafenine, ibufenac, imidazolesalicylate, indomethacin, indoprofen, isofezolac, isoladol, isonixin,ketoprofen, ketorolac, p-lactophenetide, lefetamine, loxoprofen, lysineacetylsalicylate, magnesium acetylsalicylate, methotrimeprazine,metofoline, miroprofen, morazone, morpholine salicylate, naproxen,nefopam, nifenazone, 5′ nitro-2′ propoxyacetanilide, parsalmide,perisoxal, phenacetin, phenazopyridine hydrochloride, phenocoll,phenopyrazone, phenyl acetylsalicylate, phenyl salicylate, phenyramidol,pipebuzone, piperylone, prodilidine, propacetamol, propyphenazone,proxazole, quinine salicylate, ramifenazone, rimazolium metilsulfate,salacetamide, salicin, salicylamide, salicylamide o-acetic acid,salicylsulfuric acid, salsalte, salverine, simetride, sodium salicylate,sulfamipyrine, suprofen, talniflumate, tenoxicam, terofenamate,tetradrine, tinoridine, tolfenamic acid, tolpronine, tramadol, viminol,xenbucin, zomepirac, and pharmaceutically acceptable salts thereof.

Exemplary local anesthetic therapeutic agents include, but are notlimited to, ambucaine, amolanone, amylocaine hydrochloride, benoxinate,benzocaine, betoxycaine, biphenamine, bupivacaine, butacaine, butaben,butanilicaine, butethamine, butoxycaine, carticaine, chloroprocainehydrochloride, cocaethylene, cocaine, cyclomethycaine, dibucainehydrochloride, dimethisoquin, dimethocaine, diperadon hydrochloride,dyclonine, ecgonidine, ecgonine, ethyl chloride, beta-eucaine, euprocin,fenalcomine, fomocaine, hexylcaine hydrochloride, hydroxytetracaine,isobutyl p-aminobenzoate, leucinocaine mesylate, levoxadrol, lidocaine,mepivacaine, meprylcaine, metabutoxycaine, methyl chloride, myrtecaine,naepaine, octacaine, orthocaine, oxethazaine, parethoxycaine, phenacainehydrochloride, phenol, piperocaine, piridocaine, polidocanol, pramoxine,prilocaine, procaine, propanocaine, proparacaine, propipocaine,propoxycaine hydrochloride, pseudococaine, pyrrocaine, ropavacaine,salicyl alcohol, tetracaine hydrochloride, tolycaine, trimecaine,zolamine, and pharmaceutically acceptable salts thereof.

Exemplary antispasmodic therapeutic agents include, but are not limitedto, alibendol, ambucetamide, aminopromazine, apoatropine, bevoniummethyl sulfate, bietamiverine, butaverine, butropium bromide,n-butylscopolammonium bromide, caroverine, cimetropium bromide,cinnamedrine, clebopride, coniine hydrobromide, coniine hydrochloride,cyclonium iodide, difemerine, diisopromine, dioxaphetyl butyrate,diponium bromide, drofenine, emepronium bromide, ethaverine, feclemine,fenalamide, fenoverine, fenpiprane, fenpiverinium bromide, fentoniumbromide, flavoxate, flopropione, gluconic acid, guaiactamine,hydramitrazine, hymecromone, leiopyrrole, mebeverine, moxaverine,nafiverine, octamylamine, octaverine, oxybutynin chloride,pentapiperide, phenamacide hydrochloride, phloroglucinol, pinaveriumbromide, piperilate, pipoxolan hydrochloride, pramiverin, prifiniumbromide, properidine, propivane, propyromazine, prozapine, racefemine,rociverine, spasmolytol, stilonium iodide, sultroponium, tiemoniumiodide, tiquizium bromide, tiropramide, trepibutone, tricromyl,trifolium, trimebutine, n,n-ltrimethyl-3,3-diphenyl-propylamine,tropenzile, trospium chloride, xenytropium bromide, and pharmaceuticallyacceptable salts thereof.

According to another feature, the mesh of the invention may include anysuitable end portions, such as tissue dilators, anchors, and associationmechanisms for associating the sling with a delivery device. Withoutlimitation, examples of slings, sling assemblies, sling delivery devicesand approaches, sling assembly-to-delivery device associationmechanisms, and sling anchoring mechanisms including features with whichthe sling of the invention may be employed are disclosed in U.S. Pat.No. 6,042,534, entitled “Stabilization sling for use in minimallyinvasive pelvic surgery,” U.S. Pat. No. 6,755,781, entitled “Medicalslings,” U.S. Pat. No. 6,666,817, entitled “Expandable surgical implantsand methods of using them,” U.S. Pat. No. 6,042,592, entitled “Thin softtissue surgical support mesh,” U.S. Pat. No. 6,375,662, entitled “Thinsoft tissue surgical support mesh,” U.S. Pat. No. 6,669,706, entitled“Thin soft tissue surgical support mesh,” U.S. Pat. No. 6,752,814,entitled “Devices for minimally invasive pelvic surgery,” U.S. Ser. No.10/918,123, entitled “Surgical Slings,” U.S. patent application Ser. No.10/641,3 76, entitled “Spacer for sling delivery system,” U.S. patentapplication Ser. No. 10/641,192, entitled “Medical slings,” U.S. Ser.No. 10/641,170, entitled “Medical slings,” U.S. Ser. No. 10/640,838,entitled “Medical implant,” U.S. patent application Ser. No. 10/460,112,entitled “Medical slings,” U.S. patent application Ser. No. 10/631,364,entitled “Bioabsorbable casing for surgical sling assembly,” U.S. Ser.No. 10/092,872, entitled “Medical slings,” U.S. patent application Ser.No. 10/939,191, entitled “Devices for minimally invasive pelvicsurgery,” U.S. patent application Ser. No. 101774,842, entitled “Devicesfor minimally invasive pelvic surgery,” U.S. patent application Ser. No.101774,826, entitled “Devices for minimally invasive pelvic surgery,”U.S. Ser. No. 10/015,114, entitled “Devices for minimally invasivepelvic surgery,” U.S. patent application Ser. No. 10/973,010, entitled“Systems and methods for sling delivery and placement,” U.S. patentapplication Ser. No. 10/957,926, entitled “Systems and methods fordelivering a medical implant to an anatomical location in a patient,”U.S. patent application Ser. No. 10/939,191, entitled “Devices forminimally invasive pelvic surgery,” U.S. patent application Ser. No.10/918,123, entitled “Surgical slings,” U.S. patent application Ser. No.10/832,653, entitled “Systems and methods for sling delivery andplacement,” U.S. patent application Ser. No. 10/642,397, entitled“Systems, methods and devices relating to delivery of medical implants,”U.S. patent application Ser. No. 10/642,395, entitled “Systems, methodsand devices relating to delivery of medical implants,” U.S. patentapplication Ser. No. 10/642,365, entitled “Systems, methods and devicesrelating to delivery of medical implants,” U.S. patent application Ser.No. 10/641,487, entitled “Systems, methods and devices relating todelivery of medical implants,” U.S. patent application Ser. No.10/094,352, entitled “System for implanting an implant and methodthereof,” U.S. patent application Ser. No. 10/093,498, entitled “Systemfor implanting an implant and method thereof,” U.S. patent applicationSer. No. 10/093,450, entitled “System for implanting an implant andmethod thereof,” U.S. patent application Ser. No. 10/093,424, entitled“System for implanting an implant and method thereof,” U.S. patentapplication Ser. No. 10/093,398, entitled “System for implanting animplant and method thereof,” and U.S. patent application Ser. No.10/093,371, entitled “System for implanting an implant and methodthereof” Moreover, the slings disclosed herein may be adapted for use inpelvic floor repair systems and related devices and methods. Suchsystems include, for example, those disclosed in U.S. Pat. No.6,197,036, entitled “Pelvic Floor Reconstruction,” U.S. Pat. No.6,691,711, entitled “Method of Correction of Urinary and GynecologicalPathologies Including Treatment of Incontinence,” U.S. Pat. No.6,884,212, entitled “Implantable Article and Method,” U.S. Pat. No.6,911,003, entitled “Transobturator Surgical Articles and Methods,” U.S.patent application Ser. No. 10/840,646, entitled “Method and Apparatusfor Cystocele Repair,” U.S. application 10/834,943, entitled “Method andApparatus for Treating Pelvic Organ Prolapse,” U.S. Patent ApplicationSerial No. 10/804,718, entitled “Prolapse Repair,” and U.S. patentapplication Ser. No. 11/115,655, entitled “Surgical Implants and RelatedMethods,” U.S. patent application Ser. No. 11/400,111, entitled“Systems, Devices, and Methods for Treating Pelvic Floor Disorders,” andU.S. patent application Ser. No. 11/399,913, entitled “Systems, Devices,and Methods for Sub-Urethral Support,” the entire contents of all ofwhich are incorporated herein by reference.

The foregoing embodiments are merely examples of various configurationsof the materials described and disclosed herein. Additionalconfigurations can be readily deduced from the foregoing, includingcombinations thereof, and such configurations and continuations areincluded within the scope of the invention. The specifications and otherdisclosures in the patents, patent applications, and other referencescited herein are hereby incorporated by reference in their entirety.

What is claimed is:
 1. A mesh for use in an implantable slingcomprising: a plurality of transverse strands and a plurality oflongitudinal strands arranged in a grid, and wherein at least onelongitudinal strand is biodegradable and comprises a plurality of fibersegments adapted to extend in a substantially same longitudinal path butbeing spaced apart so as to not contact a common transverse strand. 2.The mesh of claim 1, wherein the plurality of transverse strands arenon-degradable.
 3. The mesh of claim 1, wherein at least onebiodegradable strand has an inner non-degradable core disposed within anexterior degradable shell.
 4. The mesh of claim 1, comprising aplurality of biodegradable longitudinal strands.
 5. The mesh of claim 1,wherein the plurality of longitudinal strands include both biodegradableand non-degradable strands, and the plurality of transverse strandsinclude both biodegradable and non-degradable strands.
 6. The mesh ofclaim 1, wherein at least one biodegradable strand has an innernon-degradable core disposed within an exterior degradable shell.
 7. Themesh of claim 1, comprising a biodegradable fiber formed from materialthat degrades in-vivo at a rate that facilitates a predetermined rate ofscar tissue in-growth into the mesh.
 8. The mesh of claim 1, wherein theplurality of longitudinal strands includes both biodegradable andnon-degradable strands, and wherein the ratio of biodegradable tonon-degradable longitudinal strands is greater than about ¼.
 9. The meshof claim 1, wherein the plurality of longitudinal strands includes bothbiodegradable and non-degradable strands, and wherein the ratio ofbiodegradable to non-degradable longitudinal strands is in a range ofabout ¼ to about
 1. 10. The mesh of claim 1, comprising a plurality ofbiodegradable strands and a plurality of non-degradable strands, andwherein the ratio of biodegradable to non-degradable strands is greaterthan about ¼.
 11. The mesh of claim 1, comprising a plurality ofbiodegradable strands and a plurality of non-degradable strands, andwherein the ratio of biodegradable to non-degradable strands is in arange of about ¼ to about
 4. 12. The mesh of claim 1 including an agent.13. The mesh of claim 12, wherein the agent is a therapeutic agent. 14.The mesh of claim 1, wherein, upon degradation of at least one strand, agap of greater than about 50 1 lm forms in the mesh between adjacentmesh strands.
 15. The mesh of claim 1, wherein at least one transversestrand is attached to a plurality of longitudinal strands by anadhesive.
 16. The mesh of claim 1, wherein the at least one longitudinalstrand is adapted to extend along a patient's urethra.
 17. A mesh foruse in an implantable sling comprising: a plurality of transversestrands and a plurality of longitudinal strands arranged in a grid, theplurality of longitudinal strands adapted to extend along a patient'surethra, and wherein at least one of the transverse strands and at leastone of the longitudinal strands is biodegradable.
 18. The mesh of claim17, wherein a plurality of transverse strands and a plurality oflongitudinal strands are biodegradable.
 19. The mesh of claim 17,wherein at least one biodegradable strand has an inner non-degradablecore disposed within an exterior degradable shell.
 20. A method forforming a urethral support mesh comprising: providing a non-degradablemesh; providing a solution containing a bio-degradable polymer; andapplying the solution to the mesh in a pattern.